There may be no more fiercely competitive market today than enterprise mobile, with the iPhone, Android and Blackberry (among others) all jockeying for market share. Larry Barrett reports.

The latest report from IT research firm ABI Research portends both good and bad things for Research In Motion, the longtime leader in the U.S. enterprise smartphone market.

First the good news: Worldwide smartphone shipments to the enterprise are expected to grow at compounded annual growth rate of 15 percent a year through 2015, expanding an already enormous pie of which devices running RIM's (NASDAQ: RIMM) BlackBerry mobile OS will still hold the top spot at 26 percent.

The bad news is that forecast means RIM will struggle to hold off a flock of competitors in multiple regions, most notably to Apple's (NASDAQ: AAPL) iPhone and iOS and Google's (NASDAQ: GOOG) fast-ascending Android mobile OS.

Worldwide, ABI Research expects the mobile enterprise installed customer base to exceed 30 percent by 2015 and 65 percent in North America where RIM's BlackBerry will maintain its strongest foothold.